Hi,
Thank you for posting your concern.
If you want to upload offline conversions on a Google Ads test account, then I am afraid that this is not possible. The reason is GCLID is generated when an event happened on your live ads that are serving in Google networks but Google Ads test account does not serving live ads. Those GCLIDs should also be uploaded on the account where it belongs and generated.
Regards,
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| Ernie John Blanca Tacata |
| Google Ads API Team |
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